[Federal Register: April 21, 2006 (Volume 71, Number 77)]
[Proposed Rules]               
[Page 20607-20624]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]



Fish and Wildlife Service

50 CFR Part 17

Endangered and Threatened Wildlife and Plants; 12-Month Finding 
on a Petition to Delist the Pacific Coast Population of the Western 
Snowy Plover

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Notice of 12-month petition finding.


SUMMARY: We, the U.S. Fish and Wildlife Service (Service), announce a 
12-month finding on a petition to remove the Pacific coast population 
of the western snowy plover (Charadrius alexandrinus nivosus) from the 
Federal List of Threatened and Endangered Wildlife pursuant to the 
Endangered Species Act of 1973, as amended. After reviewing the best 
scientific and commercial information available, we find that the 
petitioned action is not warranted. We ask the public to submit to us 
any new information that becomes available concerning the status of, or 
threats to, the species. This information will help us monitor and 
encourage the conservation of this species.

DATES: The finding announced in this document was made on April 21, 

ADDRESSES: Data, information, comments, or questions concerning this 
finding may be sent to the Field Supervisor (Attn: WSP-DELIST), Arcata 
Fish and Wildlife Office, U.S. Fish and Wildlife Service, 1655 Heindon 
Road, Arcata, California 95521-5582 (fax: 707-822-8411). The petition 
and supporting information are available for public inspection, by 
appointment, during normal business hours, at the above address.

FOR FURTHER INFORMATION CONTACT: Jim Watkins, Fish and Wildlife 
Biologist, in Arcata (telephone: 707-822-7201).



    Section 4(b)(3)(A) of the Endangered Species Act (Act) of 1973, as 
amended (16 U.S.C. 1531 et seq.) requires that we make a finding on 
whether a petition to list, delist, or reclassify a species presents 
substantial information to indicate the petitioned action may be 
warranted. Section 4(b)(3)(B) of the Act requires that within 12 months 
after receiving a petition to revise the List of Threatened and 
Endangered Wildlife and Plants that contains substantial information 
indicating that the petitioned action may be warranted, the Secretary 
shall make one of the following findings: (a) The petitioned action is 
not warranted, (b) the petitioned action is warranted, or (c) the 
petitioned action is warranted but precluded by higher priority 
workload. Such 12-month findings are to be published promptly in the 
Federal Register.

Previous Federal Action

    The Pacific coast population of the western snowy plover 
(Charadrius alexandrinus nivosus) (Pacific Coast WSP) was listed as 
threatened on March 5, 1993 (Service 1993 (58 FR 12864)), prior to 
publication of our 1996 distinct population segment (DPS) policy 
(Service and NMFS 1996a (61 FR 4722; February 7, 1996)). At the time of 
listing, the primary threat to the plover was the loss and degradation 
of habitat from human activities. Critical habitat for the Pacific 
Coast WSP was designated on September 9, 2005 (70 FR 56969).
    On July 29, 2002, we received a petition from the Surf-Ocean Beach 
Commission of Lompoc, California, to delist the Pacific Coast WSP 
pursuant to the Act. We also received a similar petition dated May 30, 
2003, from the City of Morro Bay, California. As explained in our 1996 
Petition Management Guidance (Service and NMFS 1996b), subsequent 
petitions are treated separately only when they are greater in scope or 
broaden the area of review of the first petition. The City of Morro Bay 
petition repeats the same information provided in the Surf-Ocean Beach 
Commission petition and was therefore treated as a comment on the first 
petition received. On March 22, 2004 (69 FR 13326), we announced an 
initial (90-day) finding that the petition presented substantial 
information to indicate the petitioned action may be warranted, and we 
initiated a status review under sections 4(b)(3)(A) and 4(c)(2)(A) of 
the Act. We have now completed the status review on the species using 
the best available scientific and commercial information, and have 
reached a determination regarding the petitioned action. This status 
review also fulfills the requirements of 4(c)(2).

Species Information

    Snowy plovers are small shorebirds, about 16 centimeters (6 inches) 
long, with pale brown upperparts, buff-colored bellies, and darker 
patches on their shoulders and heads. Their dark gray to black legs are 
a useful distinguishing feature when comparing to other plover species 
(Page et al. 1995a). Two subspecies of snowy plover

[[Page 20608]]

recognized by the American Ornithological Union (AOU 1957), nest in 
North America: The western snowy plover and the Cuban snowy plover 
(Charadrius alexandrinus tenuirostis).

Biology and Distribution

    The breeding range of the western snowy plover includes sites in 
California, Oregon, Washington, Nevada, Utah, Arizona, Colorado, New 
Mexico, Kansas, Oklahoma, Texas, and Baja California, central and 
northeastern Mexico, as well as irregularly visited sites in 
Saskatchewan, Canada; and Wyoming and Montana (Page et al. 1995a) (see 
Figure 1). In 1993, we listed and defined the Pacific Coast WSP as 
those western snowy plovers ``that nest adjacent to or near tidal 
waters'' of the Pacific Ocean (Service 1993 (58 FR 12864)). In this 
finding, we refer generally to plovers nesting at locations other than 
on the Pacific coast as ``interior'' populations, even though this term 
includes populations nesting on the Gulf coast. We also refer to 
interior nesting populations according to whether they nest east or 
west of the Rocky Mountains, on the Gulf Coast, or in central Mexico.


[[Page 20609]]



[[Page 20610]]

    The second North American subspecies, the Cuban snowy plover, nests 
along the Gulf coast from Louisiana to western Florida and south 
through the Caribbean (American Ornithological Union (AOU) 1957; 
Service 1993 (58 FR 12864); Page et al. 1995a). The subspecific status 
of populations breeding east of the Rocky Mountains, now considered to 
belong to the subspecies C. a. nivosus, has been questioned. Some 
consider these populations to belong more appropriately to the 
subspecies C. a. tenuirostris (Warriner et al. 1986). Others consider 
the subspecies C. a. tenuirostris to be a paler version of the western 
snowy plover rather than a separate subspecies (Page et al. 1995a). In 
this status review, we rely on the current American Ornithological 
Union taxonomic classification that considers C. a. nivosus to be a 
valid subspecies (AOU 1957).
    Some plovers nesting on the Pacific coast migrate north or south to 
other Pacific coastal wintering sites, while others stay at their 
breeding sites year round. Birds nesting in the interior, west of the 
Rocky Mountains (the western interior population) winter in coastal 
California and Baja California, Mexico, and often commingle with the 
Pacific Coast WSP. However, some individuals from the southern 
California interior do not migrate (Page et al. 1995a). Plovers from 
the interior east of the Rockies are migratory, probably wintering on 
the Gulf Coast, except for small numbers of year-round residents in 
Texas, Arizona, and New Mexico. Plovers nesting on the Gulf coast may 
sometimes winter at other Gulf coast locations, while those nesting in 
central Mexico are likely year-round residents (Page et al. 1995a).
    The timing of the nesting season varies with location, but in 
coastal California it tends to run from March through September (Page 
et al. 1995a). Breeding locations tend to be sandy areas close to 
water, including beaches, salt pans, alkaline playas, and gravel bars 
on the tidally influenced portion of coastal rivers. Clutches, which 
most commonly consist of three eggs, are laid in shallow scrapes or 
depressions in the sand. Snowy plovers generally form monogamous pair 
bonds and share incubation duties, but western snowy plover females 
typically desert the brood shortly after hatching, and may renest with 
a new male if time remains in the season to do so. Males typically care 
for the young until they fledge, which takes about a month, and may 
then renest with a new partner if sufficient time remains in the season 
(Stenzel et al. 1994). This results in a serially polygamous breeding 
system in which males may double clutch and females may triple clutch 
during a single season (Page et al. 1995a).

Population Status

    The current known breeding range of the Pacific Coast WSP extends 
from Damon Point, Washington, to Bahia Magdelena, Baja California, 
Mexico. Observed estimates for the Pacific Coast WSP, rangewide, are 
approximately 3,700 individuals; within that total, the observed 
estimate of the U.S. population of the Pacific Coast WSP is 
approximately 1,800 adults (see Table 1) (L. Stenzel, in litt. 2004a; 
G. Page, in litt. 2005b; L. Kelly, in litt. 2006; M. Jensen, in litt. 
2006). Current population estimates are developed by multiplying the 
number of adult plovers observed during breeding window surveys (Table 
1 Observed Estimate) by a correction factor of 1.3, which adjusts the 
observed number to that of a known population (Table 1 Current 
Population Estimate). Multiplying the observed estimates by the 
correction factor, the current population estimate for the United 
States portion of the Pacific Coast WSP is approximately 2,300 (see 
Table 1), based on the 2005 breeding window survey (Stenzel, in litt. 
2004b; Page, in litt. 2005b; Jensen, in litt. 2006; Kelly, in litt. 
2006), and the current population estimate for the Pacific Coast WSP 
rangewide is approximately 4,800.

     Table 1.--Observed and Estimated Numbers of Adult Western Snowy Plovers in the United States and Mexico
                                  [Adapted and updated from Page et al. 1995a]
                                            Observed                          Observed       Current population
           Location               Year       number          Source         estimate \1\        estimate \2\
U.S. Pacific Coast...........        2005  ..........  A                  1,795             2,334.
Washington...................        2005          15  I                  ................  ....................
Oregon.......................        2005         100  H                  ................  ....................
California...................        2005       1,680  A                  ................  ....................
Mexico, West Coast of Baja      1991-1992       1,344  B, C               At least 1,900    At least 2,470.
Pacific Coast WSP Estimated Total                                         3,695             4,804.
Interior U.S., west of Rocky
    All States except Utah...        1988  ..........  C                  6,100             7,930.
    Nevada...................        1988         691  C                  ................  ....................
    Oregon...................        1988         552  C                  ................  ....................
    Great Basin..............        1988       1,213  C                  ................  ....................
    San Joaquin Valley.......        1988         241  C                  ................  ....................
    S. California deserts....        1988         291  C                  ................  ....................
Utah.........................        1992       1,501  D                  4,189             5,445.
Great Plains:
    Colorado.................     1986-92  ..........  C, G               Up to 150         Up to 195.
    Kansas...................     1986-92  ..........  C, G               Up to 356         Up to 463.
    Oklahoma.................     1986-92  ..........  C, G               2,007             2,609.
    Texas....................     1986-92  ..........  C, G               500               650.
    New Mexico...............     1986-92  ..........  C, G               Up to 500         Up to 650.
Gulf Coast:
    Texas....................        2004  ..........  E                  1,000             1,300.
    NE Mexico................        1992  ..........  G                  Up to 34          Up to 44.
Interior Mexico..............        1994  ..........  F                  At least 35       At least 46.

[[Page 20611]]

    Presa Acecatecana........  ..........          12  .................  ................  ....................
    Salinas de Hidalgo.......  ..........          16  .................  ................  ....................
    Jalisco (near Atoyac)....  ..........           6  .................  ................  ....................
    Lago Texcoco.............  ..........           1  .................  ................  ....................
Estimated Total for Interior and Gulf Coast Breeding WSP                  14,871            19,332.
Estimated Grand Total for the Subspecies                                  18,566            24,136.
\1\ The Observed Estimate (Obs. Est.) is approximated for the Mexico portion of the range based upon the
  research conducted by Page et al. (1995a).
\2\ The 2005 Current Population Est. equals the Obs. Est. multiplied by a correction factor of 1.3. The Obs.
  Est. often under counts the actual number of birds. Research by the Point Reyes Bird Observatory shows a
  correction factor is needed to give a more accurate population count (Stenzel in litt. 2004a).
Sources: A = G. Page in litt. 2005; B = E. Palacios et al. 1994; C = G. Page et al. 1995a; D = P. Paton in litt.
  2004; E = Zdravkovic 2004; F = Howell and Webb 1994; G = Gorman and Haig 2002; H = L. Kelly in litt. 2006; I =
  M. Jensen in litt. 2006.

    Recent census data for the Baja California, Mexico population of 
the Pacific Coast WSP do not exist; however, we use the observed 
estimate of 1,900 adults as provided in Page et al. (1995a), as that is 
the best available information. The population is sparse in Washington, 
Oregon, and northern California. Historical records indicate that 
nesting plovers were once more widely distributed and abundant in 
coastal Washington, Oregon, and California than at present (Page et al. 
1995a). At about the time the species was listed under the Act, 
approximately 2,000 western snowy plovers bred along the United States 
Pacific Coast (Page et al. 1995a) and approximately 1,900 bred on the 
west coast of Baja California, Mexico (Palacios et al. 1994). The 
largest number of breeding birds occurred from south San Francisco Bay 
to southern Baja California (Page and Stenzel 1981; Palacios et al. 
    Washington--Occupancy of Sites: In Washington, plovers formerly 
nested at five coastal sites (Washington Department of Fish and 
Wildlife 1995). Three of these remain currently active, indicating a 40 
percent decline in the number of Washington breeding areas. Occupancy 
at sites in Washington has declined for several reasons, including site 
degradation due to beach erosion (e.g., Westport Spit, Leadbetter 
Point, Gunpowder Sands Island). Subsequent to the 1993 listing, habitat 
conditions have improved or expanded at other sites (e.g., Midway 
    Washington--Number of Pacific Coast WSP: The number of birds in 
Washington, however, appear to be stable to increasing since the early 
1990s, based on consistent, intensive, repeatable counts of adults 
during the breeding season. Breeding season surveys indicate a general 
increase in the plover breeding population since 1995 (Washington Dept. 
of Fish and Wildlife, in litt. 2003). Population numbers range from a 
low of 19 adults in 1994, to 68 in 2003. In recent years, sand has 
built up at Midway Beach creating high quality habitat, and nesting was 
documented in 1998 (Richardson et al. 2000). Uniquely banded plovers 
from natal locations along the Oregon and California coasts have bred 
in Washington coastal sites, adding to the overall breeding population 
within the State. We attribute the increases to improved coastal 
habitat at some locations, and intensive management in Oregon and 
    Oregon--Occupancy of Sites: In Oregon, plovers historically nested 
at 29 coastal locations. Our 1993 listing decision was based, in part, 
on the loss of 23 of those locations (Service 1993 (58 FR 12864)). 
However, in 2004, the number of breeding sites had increased to 10 due 
to the reoccupation of 4 historic sites (D. Lauten, in litt. 2004). As 
a result, 65 percent (19 of 29) of the historic nesting locations have 
been lost; improved from 79 percent at the time of listing.
    Oregon--Number of Pacific Coast WSP: Annual surveys of adult and 
juvenile plovers in coastal Oregon began in 1978, with intensive 
monitoring beginning in 1993. Survey data shows a general decline in 
breeding adults throughout coastal Oregon until 1994, at which time the 
trend reversed to an increase in breeding adults. Although the overall 
breeding population trend is still down from historical numbers, the 
period from 1994 to present has shown a slight increase (J. Baldwin, in 
litt. 2004). Plovers from California have been observed nesting in 
coastal Oregon, contributing to the State's breeding population, 
estimated at 110 birds in 2003 (Oregon Department of Parks and 
Recreation 2003). Eighty-three plovers were observed during breeding 
surveys in 2004, and 100 were counted during the 2005 breeding season 
(Lauten et al. 2006). We attribute the increase directly to protections 
and resultant management from the 1993 Federal listing. Management 
measures benefiting plovers include the use of exclosures to reduce 
nest predation, restoration of breeding habitat by removing European 
beachgrass (Ammophila arenaria), increased use of signs and symbolic 
fencing (temporary post and cable) around breeding sites, intensified 
public information, and enhanced law enforcement.
    California--Occupancy of Sites: Eight geographic areas in 
California support over three-quarters of the Statewide coastal 
breeding population (Page et al. 1991). By the late 1970s, nesting 
plovers in California were absent from 33 of 53 of the breeding 
locations having breeding records prior to 1970 (Page and Stenzel 
1981). Stenzel (in litt. 2004b) has subsequently identified an 
additional 11 locations that have lost nesting plovers. An estimated 
1,566 adult plovers were seen during initial Statewide coastal surveys 
by Point Reyes Bird Observatory (PRBO) during the 1977 to 1980 breeding 
seasons (Page and Stenzel 1981). The surveys indicated that by 1980, 
plovers had been extirpated or severely reduced in breeding 
distribution throughout substantial portions of their coastal southern 
California breeding range, especially in San Diego, Orange, and Los 
Angeles Counties. With the exception of some beach segments along

[[Page 20612]]

Monterey Bay in Monterey County, breeding plovers were absent or 
severely reduced at other historic breeding sites along the southern 
and central California coast. A preliminary analysis of current 
breeding sites identifies 10 new, low-density breeding locations (L. 
Stenzel, in litt. 2004b). However, analysis also shows that at least 44 
of the historic sites, many of which were known to be high-density 
sites, have not had any recent nesting activity (L. Stenzel, in litt. 
2004a; 2004b).
    California--Number of Pacific Coast WSP: In addition to losses of 
breeding locations, or lack of activity at breeding locations, 
Statewide beach surveys conducted by PRBO during 1989 and 1991 also 
indicated a decline in numbers of breeding plovers. Along the 
California coast, including the Channel Islands, plover numbers 
declined by almost 5 percent, and the estimated decline at San 
Francisco Bay was about 40 percent (A. Powell, pers. comm. 1998; Point 
Reyes Bird Observatory, unpublished data). More recent surveys during 
the breeding seasons of 2000, 2002, 2003, 2004, and 2005, were 
accomplished through a collaboration of researchers studying plovers in 
coastal California. Results are provided in Table 2, below.

                       Table 2.--Total Number of Adult Snowy Plovers During Breeding Season Window Surveys of the California Coast
                          Year                                \1\      1989 \2\    1991 \3\    2000 \3\    2002 \3\    2003 \3\    2004 \3\    2005 \4\
Total...................................................      1,566       1,386       1,371         976       1,387       1,444       1,904      1,680
\1\ Page and Stenzel 1981--Surveys were conducted in multiple years; \2\ Page et al. 1991; \3\ L. Stenzel, in litt. 2004a; \4\ Page in litt. 2005.

    In 2000, there were 976 breeding adult plovers observed in coastal 
California. Surveyors observed 1,387 and 1,444 adult plovers during 
similar breeding season surveys conducted in 2002 and 2003, 
respectively. Statewide breeding season window surveys for California 
demonstrate an increase in observed breeders from 2001 through 2005, 
although there is still an overall decline when compared to historic 
breeding population numbers (J. Baldwin, in litt. 2004; K. Lafferty, in 
litt. 2002).
    The increase in the number of adult plovers observed during 
breeding season window surveys in the southern part of California is 
related, at least in part, to protections and associated management 
provided to the federally endangered California least tern (Sterna 
antillarum browni) (Persons and Applegate 1996). Predator management, 
habitat restoration, leash laws, controlled recreational vehicle use, 
symbolic fencing, and other measures have contributed to the Statewide 
increase in breeding Pacific Coast WSP and also provided benefits to 
interior plovers wintering on the coast.
    Baja California, Mexico--Occupancy of Sites and Number of Pacific 
Coast WSP: Along the Pacific coast of Baja California, Mexico, most 
plover nesting areas are associated with the largest wetlands. A survey 
of breeding western snowy plovers along the Pacific coast of Baja 
California between 1991 and 1992 found 1,344 adults, mostly at four 
coastal wetland complexes: Bahia San Quintin, Lagunas Ojo de Liebre and 
Guerrero Negro, Laguna San Ignacio, and Bahia Magdalena (Palacios et 
al. 1994). Based on detection ratios established for surveys on the 
United States Pacific coast, this indicated a coastal Baja population 
of at least 1,900 adults (Palacios et al. 1994; Page et al. 1995a). We 
have no information of any more recent estimates (E. Palacios, in litt. 

Discussion of the Petition

    The petition asserts that the Pacific Coast WSP does not meet the 
Act's definition of a threatened species as its population is in flux 
rather than decline. The petition offers a table and a graph to support 
this assertion: The graph in section 5.1.2 of the petition provides 
breeding population counts for Vandenberg Air Force Base (VAFB) for 
1978 through 2001, and the table in section 5.1 (included as part of 
Table 2 above) provides breeding population census counts for the 
California coast during 6 years from 1980 to 2000. The graph shows VAFB 
breeding population fluctuating in size from more than 100 to about 20 
between 1978 and 2001.
    The petition states that the VAFB data reflect dramatic 
fluctuations that can occur within the plover population. Vandenberg 
has two sections of beach that support plover breeding known as North 
Beach and South Beach. The graph presented within the petition 
(subsection 5.1.2) shows that Vandenberg's plover population has 
fluctuated dramatically, with an overall increase from 119 birds in 
1978 to 121 birds in 2001 (Surf Ocean Beach Commission 2002). However, 
the petition does not provide the sources for the data in the graph. We 
believe the data in the petition's graph from 1993 to 2001 are from 
annual plover monitoring reports that VAFB started in 1993 (e.g., 
Persons 1994; Hickey and Page 2001) because we know of no other source 
from which the information could have come.
    It appears that the 1978 data in the petition's graph are from Page 
and Stenzel (1981), but it is not clear upon what the intermittent 
counts presented in the graph between 1978 and 1993 are based. This 
graph shows a population increase from 193 to 239 breeding adults over 
the years 1993 to 1997, a decrease to 132 and then 78 adults in 1998 
and 1999 following severe storms and an oil spill in the winter of 1997 
through 1998, and then a slow increase up to 122 adults in 2001. The 
VAFB monitoring reports also note generally increasing efforts to 
exclude human interference with nesting during these years. Based on 
these data alone, it appears that plover breeding numbers can be 
seriously affected by random natural events such as heavy storms, but 
this does not support the petition's conclusion that the plover 
population is in flux rather than decline. The 1978 data, which 
petitioners offer as evidence of an overall increase of 119 to 121 
birds, was itself collected after heavy winter storms. These storms 
were so severe that only 7.1 mi (11.5 km) of beach were available for 
nesting (Page and Stenzel 1981; L. Stenzel, pers. comm. 2003); in 
contrast, in 2001, 12.5 linear miles (mi) [20.1 linear kilometers (km)] 
of beach were available for nesting (Hickey and Page 2001). The 1978 
numbers would therefore likely have been depressed from historic 
levels, and would constitute poor support for the petition's 
conclusions regarding overall population trends. More importantly, we 
do not consider census data from VAFB alone to reasonably support 
conclusions concerning the entire Pacific coast population. Pacific 
Coast WSP do occasionally nest or renest at other coastal locations 
(Stenzel et al. 1994; Page et al. 1995a), so fluctuations in the VAFB 
breeding population could either be caused or moderated by

[[Page 20613]]

immigration to and emigration from other beaches.
    The table in section 5.1 of the petition provides census data for 
the California coast and serves as a better indication of population 
trends for the Pacific Coast WSP, because ``the California coast 
population represents at least 90 percent of the listed Pacific coast 
population in the United States'' (D. Noda, in litt. 2001) (see table 
1). Yet, the data presented in this petition table show a steady 
decrease in population from 1980 to 2000 except for a particularly high 
count in 1997 and a somewhat low count in 1995. The 1997 and 1995 
surveys were both conducted differently than those for other years and 
are therefore not directly comparable to other years. The 1995 census 
did not include counts from several important breeding sites such as 
South San Francisco Bay (P. Nieto, SRS Technologies, in litt. 2002; L. 
Stenzel in litt. 2004a; G. Page, pers comm. 2003). The 1997 population 
estimate is based on intensive monitoring information for some areas 
combined with ``corrected'' window survey data from previous years for 
other areas (Nur et al. 1999; G. Page, pers. comm. 2003). All other 
population estimates in the petition's table in section 5.1 are totals 
of window survey counts from the known breeding sites.
    We developed Table 2 (above) to show California coastal population 
estimates based on the observed number of adult plovers during breeding 
season window surveys. Table 2 consists of the population counts 
reported in the petition's table for years other than 1995 and 1997, 
along with population counts from 2002 through 2005 which we added to 
the Table.
    The increase first observed in 2002 is encouraging, and we 
attribute the population increases to the implementation of 
conservation strategies by our recovery implementation stakeholders, 
such as California State Parks, who have engaged in habitat restoration 
and the use of extensive symbolic fencing. It is also important to note 
that the population level documented by Page and Stenzel (1981), was 
likely depressed by severe storms and resulting beach erosion during 
the winter of 1977 through 1978 (Page and Stenzel 1981). Counts 
conducted at VAFB from 1998 through 2000 showed a drop in adult plover 
numbers from 238 to 132 following similarly severe storms during the 
winter of 1997/1998 (Applegate and Schultz 1999; Applegate and Schultz 
2000). Although the survey conducted in 1977 through 1980 provided 
fairly high population estimates, Page and Stenzel (1981) noted: 
``Numbers have definitely declined on the coast; the species was not 
found breeding in 33 of the 53 locations with breeding records prior to 
1970. Of the 33 areas, 28 are not likely to have regular breeding 
populations again because the habitat has been destroyed or human use 
of the area is too great.'' The petition interprets such conclusions as 
speculative since they were not based on census data and do not show 
how often particular breeding sites were used. While we agree that any 
precise population estimates based on such data would be speculative, 
we believe the indications of lost habitat provided by Page and Stenzel 
(1981) are well supported and reasonably lead to the conclusion that 
historic population levels were higher than those documented in the 
1977 to 1980 census. We therefore consider the available data on the 
coastal California population to provide more support for the 
contention that the Pacific Coast WSP has declined from historical 
    The listing decision was also based on the loss of 33 California 
breeding sites. An additional 11 sites have been subsequently 
identified as having also lost nesting plovers since the original work 
was completed and reported in the listing decision (L. Stenzel, in 
litt. 2004b). Consequently, the loss of 44 of 53 breeding sites in 
California represents an 83 percent reduction in historical nest 
locations. Some of those sites in southern California were especially 
significant. Places like Los Angeles County, where 25 miles of former 
breeding habitat were lost, may have supported up to 600 pairs (1200 
breeding birds) of plovers. The estimate is extrapolated from an egg 
collector's 1903 record of 50 pairs along a 2 mile section of Manhattan 
Beach (L. Stenzel, in litt. 2004b). At the time of the 1993 listing, 
Oregon had lost 79 percent (23 of 29) of its historic nesting sites, 
and Washington had lost 40 percent of its nesting locations (2 of 5) 
(Service 1993 (58 FR 12864)). Additionally, the remaining habitat has 
been degraded by the colonization of nonnative European beach grass by 
occupying nesting substrate and changing from the open structure that 
plovers prefer, increased number of predators, and increased human use. 
Addressing the above three factors through effective management range-
wide and the reestablishment of 4 former breeding sites in Oregon (D. 
Lauten, in litt. 2004) have bolstered plover populations since listing 
(G. Page, in litt. 2004a).
    The petition also cites a recent Pacific Coast WSP viability 
analysis that indicates the population would likely remain above an 
``extinction threshold'' of 50 individuals for at least 100 years under 
the 1999 status quo (Nur et al. 1999). However, the petition did not 
note that the ``status quo'' scenario (Scenario 1) assumed that 
existing protections and management actions under the Act would 
continue and projected a significant downward trend in population over 
the next 100 years in the absence of additional efforts. Under a ``no 
management'' scenario (Scenario 12), the analysis found a 51 percent 
probability of reaching an extinction threshold after 100 years. The 
analysis did not consider a scenario involving the complete removal of 
protections under the Act. We therefore do not consider the petition's 
statement that the Pacific Coast WSP population is healthy but in flux 
to be well supported by available data, especially if protections under 
the Act are removed.

Distinct Population Segment

    In a 12-month finding, we must determine if: (1) The petitioned 
action is warranted; (2) the petitioned action is not warranted; or (3) 
the petitioned action is warranted but precluded by other higher 
priority activities. Under the Act, a species is defined as including 
any subspecies and any distinct population segment of a vertebrate 
species (16 U.S.C. 1532). To implement the measures prescribed by the 
Act and its Congressional guidance, we and the National Marine 
Fisheries Service (National Oceanic and Atmospheric Administration-
Fisheries), developed a joint policy that addresses the recognition of 
DPSs of vertebrate species for potential listing actions (Service and 
NMFS 1996a (61 FR 4722)). The policy allows for a more refined 
application of the Act that better reflects the biological needs of the 
taxon being considered, and avoids the inclusion of entities that do 
not require its protective measures. As noted above, in 1993, we listed 
the Pacific Coast population of the WSP as threatened. As this was 
prior to our 1996 DPS policy, a first step in this status review 
process is to review the available information to assess whether the 
Pacific Coast WSP 1993 listing determination is consistent with the 
1996 DPS policy.
    The DPS policy specifies that we are to use three elements to 
assess whether a population segment under consideration for listing may 
be recognized as a DPS: (1) The population segment's discreteness from 
the remainder of the species to which it belongs; and (2) the 
significance of the population segment to the species to which it 
belongs; and (3) the population segment's conservation status in 
relation to the ESA's standard for listing (61 FR

[[Page 20614]]

4722, 4725). If we determine that a population segment meets the 
discreteness and significance standards, then the level of threat to 
that population segment is evaluated based on the five listing factors 
established by section 4(a) of the Act to determine whether listing the 
DPS as either threatened or endangered is warranted. The DPS policy 
also states: ``Listing, delisting, or reclassifying distinct vertebrate 
population segments may allow the Services to protect and conserve 
species and the ecosystems upon which they depend before large-scale 
decline occurs that would necessitate listing a species or subspecies 
throughout its entire range. This may allow protection and recovery of 
declining organisms in a more timely and less costly manner, and on a 
smaller scale than the more costly and extensive efforts that might be 
needed to recover an entire species or subspecies'' (61 FR 4722, 4725). 
Below, we address under our DPS policy the population segment of the 
WSP currently listed as a DPS that occurs within 50 miles of the 
Pacific coast in Oregon, Washington, California, and Mexico.


    The DPS policy states that a vertebrate population segment may be 
considered discrete if it satisfies either of the following two 
    1. It is markedly separated from other populations of the same 
taxon as a consequence of physical, physiological, ecological, or 
behavioral factors. Quantitative measures of genetic or morphological 
discontinuity may provide evidence of this separation; or
    2. It is delimited by international governmental boundaries within 
which differences in control of exploitation, management of habitat, 
conservation status, or regulatory mechanisms exist that are 
significant in light of section 4(a)(1)(D) of the Act.
    The following discussion addresses only the first condition, since 
the Pacific Coast WSP DPS includes plovers within Baja California, 
Mexico and is not delimited by an international boundary.
    The 1993 listing rule stated that the Pacific Coast WSP is 
``genetically isolated'' from the interior breeding populations (58 FR 
12864). We based this conclusion on banding and monitoring data, not 
genetic data. At the time of listing, we assumed the reproductive 
separation indicated by the banding data, over time, could lead to 
genetic differentiation. Genetic data for the western snowy plover was 
not available in 1993.
    In this status review process, we examine the best information now 
available, which includes banding, monitoring, and genetic information, 
and assess the petition's additional points on discreteness, to 
determine if the 1993 listing determination was consistent with the 
1996 DPS policy. Western snowy plovers from populations in the eastern 
interior (east of the Rockies), the Gulf Coast, and the Mexican 
interior are not likely to interact with the Pacific Coast WSP, and are 
not known to visit the Pacific coast (Page et al. 1995a). We thus focus 
our discreteness analysis on the Western snowy plovers from populations 
in the western interior (west of the Rockies), and the Pacific Coast 

Banding and Monitoring Information

    Banding and monitoring studies are useful methods for evaluating 
the discreteness of two populations provided that the banding effort 
adequately samples each population, and the monitoring effort is 
adequate to provide reasonable probabilities of detecting banded 
individuals (J. Plissner, in litt. 2005). Several banding and 
monitoring studies have been conducted that address the Pacific Coast 
WSP (Spear 1979; Stenzel and Peaslee 1979; Henderson and Page 1979; 
Widrig 1980; Page and Stenzel 1981; Page et al. 1983; Wilson-Jacobs and 
Meslow 1984; Warriner et al. 1986; Herman et al. 1988; G. Page, in 
litt. 1989; Page and Bruce 1989; Stern et al. 1990a, 1990b, 1991a, 
1991b; Page et al. 1991; ODFW 1994; Palacios et al. 1994; Paton 1994; 
Persons 1994, 1995; Stenzel et al. 1994; Page et al. 1995b; G. Page et 
al., Point Reyes Bird Observatory (PRBO), in litt. 2002; Powell et al. 
2002; C. Sandoval, in litt. 2002; G. Page, PRBO, in litt. 2004b; G. 
Page, PRBO, in litt. 2005). Some of these studies were not specifically 
designed for the purpose of evaluating the discreteness of the Pacific 
Coast WSP, but nonetheless provide useful information for this 
    In this finding, we rely primarily on the banding and resighting 
efforts conducted during the period of 1984 through 1993, as this is 
the period when banding efforts were underway at several areas on the 
Pacific coast and in the western interior, and nest monitoring studies 
and breeding season surveys were underway at many locations when banded 
birds could be detected. Interior populations have not been banded 
since 1993 (L. Stenzel, in litt. 2005). From 1984 through 1993, a total 
of 4,170 plover chicks and breeding adults were banded at nine sites on 
the Pacific coast (3,077 banded birds), and at four western interior 
locations (1,093 banded birds) (G. Page, in litt. 2004b). The coastal 
locations included sites in both Oregon and central California, while 
the western interior locations included sites in Utah, Oregon, and 
    Subsequent nest monitoring and breeding season surveys conducted in 
the Pacific coast and western interior breeding zones from 1985 through 
1995 provided an opportunity for resightings of banded birds. During 
that time, a total of 22 U.S. coastal surveys; 1 coastal Baja 
California, Mexico survey; and 4 western interior surveys were 
conducted, many of which were repeated over several years (Palacios et 
al. 1994; G. Page, in litt. 2004b). Collectively, these surveys covered 
essentially the entire extent of U.S. coastal breeding habitat, as well 
as extensive portions of western interior and Baja California, Mexico 
coastal habitat, though not all such locations were surveyed every year 
(Palacios et al. 1994). During this same time period, 10 U.S. coastal 
and 4 western interior nesting studies were also conducted at sites 
along the entire Oregon Coast, Utah, eastern Oregon, and numerous 
locations on the California coast and interior (G. Page, in litt. 
2004b). Nesting studies involve repeated searching and monitoring of 
nests and nesting areas over the course of at least one breeding 
season, and are more comprehensive than surveys.
    A total of 907 banded plovers were detected by these breeding 
surveys and studies. It is important to note that this figure does not 
include plovers that were resighted in their original region (coastal 
or western interior) without evidence of nesting, and does not include 
plovers that were banded on the coast during the winter, as their 
breeding range could not be established. The total does include six 
plovers that were found nesting in more than one location, and so were 
counted twice. Of these 907 resighted plovers, only 13 (1.4 percent) 
were found in a geographic area (coastal or western interior) that was 
different from their original breeding range. Two of those 13 plovers 
(0.2 percent of the total 907 birds) were found nesting outside of 
their original breeding range. One of these two plovers, a coastal 
female nesting at the Kesterson National Wildlife Refuge in 1986, was 
one of the two birds mentioned in the original listing rule (Service 
1993 (58 FR 12864)). The other was a male banded in the interior 
(though never found nesting in the western interior) and later found 
nesting on the coast in 1995. The other 11 plovers were all coastally 
banded and found in the interior without nests (G. Page, in litt. 

[[Page 20615]]

    In addition to the 1984 through 1993 period, the period from 1977 
through 1983 provides another opportunity to detect movements between 
the western interior and Pacific Coast WSP populations. However, 
surveys were less comprehensive during this time period, and only one 
banding study took place in the western interior. Therefore, this 
period is less useful for assessing breeding dispersal, but still 
provides additional relevant information. During this period, 599 
plovers were banded at seven sites along the central California coast, 
and 400 were banded in the western interior at Mono Lake, California 
(G. Page, in litt. 2004b). The coastal survey effort included seven 
breeding season surveys across the U.S. range of the coastal 
population, as well as seven nest monitoring studies from Marin to San 
Luis Obispo Counties, California. The interior survey effort included 
three breeding season surveys, as well as the ongoing banding studies 
at Mono Lake (L. Stenzel, pers. comm. 2004). None of the plovers banded 
at Mono Lake were observed on the coast during the breeding season. One 
female, banded as a chick at Monterey Bay along the California coast, 
was found nesting at Mono Lake in 1978. This was the first of the two 
females mentioned in our original listing determination (Service 1993 
(58 FR 12864)) as having bred outside the coastal population.
    In addition to colored bands, whose combinations were administered 
by the Point Reyes Bird Observatory (PRBO), some studies employed metal 
bands administered by the Patuxent Bird Banding Lab. Resightings of 
these bands were less common, since recapture of the bird is generally 
required to read the band number. Of the 304 band retrievals reported 
to Patuxent Bird Banding Lab for years 1969 to 2002, one male was found 
to have moved from the Pacific coast to an interior location. This 
plover was banded during the non-breeding season (November 1984) near 
Ano Nuevo, California, and retrieved during the breeding season (June 
1988) near Lake Albert, Oregon (G. Goldsmith, in litt. 2004). The 
banding dates and associated migration suggest that the plover was an 
interior bird overwintering on the California coast. The age of the 
plover was unknown at the time of banding. There are no records in this 
data set of plovers moving in the opposite direction, from the western 
interior to Pacific coast.

Review of Banding Data

    We asked six researchers familiar with avian banding studies to 
examine the available banding data for the Pacific Coast WSP and 
plovers from the interior west of the Rocky Mountains, and provide us 
their professional opinions about the adequacy of those studies for 
determining reproductive separation between the two populations. Four 
of the reviewers responded. Three concluded that there appears to be 
little exchange of reproductive individuals between the western 
interior and coastal sites (G. Smith, USGS, in litt. 2004; B. Andres, 
Service, in litt. 2005; J. Plissner, ABR Inc., in litt. 2005). However, 
three of the reviewers (the fourth reviewer and two of the three 
reviewers mentioned above) also noted that because monitoring in the 
interior had been less comprehensive than on the coast, there is more 
uncertainty about the ability to detect coastal plovers that may have 
moved to the interior (B. Andres, in litt. 2005; C. Elphic, University 
of Connecticut, in litt. 2005; J. Plissner, in litt. 2005). They felt 
it was possible that a coastal breeding plover could move to the 
interior undetected, but it was highly unlikely that an interior 
breeding plover could move to the coast without being observed, as the 
coastal resighting efforts were more extensive temporally and 
geographically than those at interior sites. These three reviewers 
stated that the available data are adequate to conclude that there is 
little interaction between the breeding coastal and interior 
populations. One reviewer noted dispersal between inland and coastal 
populations may be episodic and associated with temporal variation in 
breeding conditions at regional scales, and that the banding efforts 
have not been extensive enough to address this possibility for the 
range of conditions (J. Plissner, in litt. 2005).

Conclusion on Banding Data

    We find that the existing banding and resighting data are 
sufficient to document that the Pacific Coast WSP and the western 
interior breeding populations experience limited or rare reproductive 
interchange. We are most confident in the data from the 12-year period 
1983 through 1995, as that is the period with the most extensive 
banding studies and search efforts. The results from that period 
indicate that 98.6 percent of the sampled plovers were observed during 
the breeding season using the same breeding range as where they were 
originally banded. We consider the results from that period sufficient 
to document a marked separation of breeding ranges, and illustrate that 
the amount of interchange between coastal and western interior 
populations is likely to be extremely low, though not zero. Results 
from the 1977 through 1984 period and the Patuxent banding data are 
also consistent with this conclusion. Our DPS policy does not require 
complete reproductive isolation, and allows for some limited 
interchange among population segments considered to be discrete 
(Service and NMFS 1996a (61 FR 4722)). Based on the results of these 
banding and monitoring data, we conclude that the Pacific Coast WSP is 
not freely interbreeding with other members of the taxon, although some 
genetic interchange likely occurs at a very small rate. This 
constitutes a marked separation due to breeding behavior.
    The banding data also indicate that interior nesting plovers 
overwintering on the Pacific coast are likely to be obligatory 
migrants, whereas many individuals in the Pacific Coast WSP either do 
not migrate, or do so only for short distances along the coast (Page et 
al. 1995a). This behavioral difference tends to set Pacific Coast WSP 
individuals apart from the interior birds with which they may mix 
during the winter.

Additional Points on Discreteness

    The petition asserts that the Pacific Coast WSP is not highly 
isolated, and provides VAFB monitoring records from 1993 to 1999 as 
supporting documentation to demonstrate that the Pacific Coast WSP and 
western interior populations commonly interbreed. VAFB is a coastal 
Santa Barbara County breeding site. The petition contains a table 
summarizing the VAFB survey records and indicating that during 1993 to 
1999, 90 plovers present during the breeding season had hatched 
elsewhere. However, our analysis below of the VAFB monitoring records 
supports a different conclusion than that reached by the petitioners 
and instead provides additional evidence demonstrating that coastal and 
interior populations do not commonly interbreed.
    Two of the 90 non-local birds cited in the VAFB monitoring records 
came from the western interior. These two plovers were banded at Abert 
Lake (in interior Oregon) (Stern et al. 1990a) during the 1988 through 
1989 banding season and were sighted at VAFB (on the California coast) 
on July 29, and August 19, 1993, during the breeding season (Persons 
1994). However, as noted by Persons (1994), post-breeding migration of 
plovers typically begins in early July, so only late June censuses 
accurately reflect the size of the breeding population. Later censuses 
include many non-breeding plovers. Stenzel et al. (1994) also report 
that after the first few days of July, plovers that move into a 
breeding area do not nest in the area. Therefore, sightings made only 
after the

[[Page 20616]]

first week in July, unless supported by evidence of breeding, are not 
good evidence of population interchange.
    The other 88 plovers in the VAFB monitoring records had all hatched 
on the coast, and were, therefore, also members of the coastal 
population (Stenzel et al. 1994). Such data tend to support our 
determination that the Pacific Coast WSP is discrete, as these data 
show that coastal population members tend to interbreed among 
themselves rather than with interior birds. These results are also 
consistent with additional studies, which found western snowy plovers 
renesting in new locations after having either lost or successfully 
fledged their first clutch (Warriner et al. 1986; Stenzel et al. 1994). 
For the Pacific Coast WSP, it is also common for one partner, usually 
the female, to abandon a brood between hatching and fledging and to 
start a new clutch in a new location with a new partner. Distances 
traveled to new nesting locations range from meters to hundreds of 
kilometers (Warriner et al. 1986; Stenzel et al. 1994). However, no 
such mid-season location changes have been shown to result in nesting 
at both coastal and interior sites.


    Evidence of genetic distinctness can inform our analysis of the 
discreteness of a population. In determining whether the test for 
discreteness has been met under our DPS policy, we consider available 
genetic evidence, but such evidence is not required to recognize a DPS. 
The petition questions the validity and effectiveness of using banding 
studies, as compared to genetics, for investigating levels of gene 
flow. When conducted properly, we find that both banding and genetics 
studies provide useful information. The petition relies heavily on a 
master's thesis (Gorman 2000) that did not find evidence of genetic 
differentiation between the Pacific Coast WSP and western interior 
snowy plover populations using mitochondrial DNA (mt DNA).
    Several commenters also pointed out that mtDNA markers in Gorman's 
study may have been indicating interbreeding that happened thousands of 
years ago and suggested that additional studies using a marker with a 
finer resolution, such as microsatellite comparisons, should be 
conducted (B. Crespi, in litt. 2002; J. Neigel, in litt. 2004; B. 
Foster, in litt. 2004; L. Gorman, in litt. 2004). In fact, a more 
recent study by Funk et al. (2006) includes analysis of microsatellite 
DNA markers. Funk et al. (2006) found no statistically significant 
genetic differentiation between Pacific Coast WSP and western interior 
snowy plover populations using mtDNA and microsatellite DNA markers.
    Given these available data indicating that the mtDNA and 
microsatellite data show no evidence of significant genetic 
differentiation between Pacific Coast and interior WSP populations, the 
Service's responsibility is to interpret the result in terms of our DPS 
policy. As noted in Funk et al. (2006), ``only a few dispersers per 
generation are necessary to homogenize gene pools between breeding 
habitats (Wright 1931; Slatkin 1985, 1987; Mills and Allendorf 1996).'' 
Therefore, failure to identify genetic differences between Pacific 
Coast and western interior plovers does not necessarily mean that there 
is a large amount of movement between the two areas. Movement of just a 
few individuals may prevent genetic differentiation, but movement of a 
few individuals may not be sufficient to maintain significant 
demographic connectivity (Funk et al. 2006).
    Thus, the two regions (in this case, the Pacific Coast and western 
interior populations) may continue to function as demographically 
independent populations despite sufficient gene flow to homogenize gene 
pools (which may require just a few individuals per generation) (Funk 
et al. 2006). That the two may be demographically independent, as noted 
by Funk et al. (2006), is particularly likely given that they have 
unique habitats (e.g., Pacific Coast birds tend to occur, with some 
exceptions, on open sandy beaches adjacent to the Pacific Ocean, while 
Great Basin birds occur on sand/salt flats on alkali lakes of the Great 
Basin (Page et al. 1995), low dispersal rates (Page, in litt. 2004a), 
and population declines (Page et al. 1991). Funk et al. (2006) suggest, 
for example, that ``if a Pacific Coast population of snowy plovers went 
extinct, a few immigrants from the Great Basin [interior] may not be 
sufficient to recolonize the empty habitat patch.'' They further 
suggest that empty patches of Pacific Coast habitat are not currently 
being recolonized in this fashion and that there is no reason to expect 
they would be recolonized in the future when habitat is even further 
    In summary, the genetic information available to us in Gorman 
(2000) and Funk et al. (2006) shows no evidence of genetic 
differentiation between Pacific Coast and western interior WSP, using 
mtDNA and microsatellite markers. For this reason, we do not find that 
the genetics data currently available to us provide evidence that 
Pacific Coast WSP is ``markedly separated'' from western interior 
populations of WSP. However, as outlined above and articulated in Funk 
et al. (2006), it is reasonable to conclude that other data (i.e., 
besides genetic data) are relevant to an analysis of whether WSP from 
these two geographic regions can be considered ``markedly separated'' 
(i.e., discrete) per our DPS policy. As noted above in the Banding and 
Monitoring Information section, we believe there is substantial 
evidence from banding data to indicate that exchange of individuals 
between the Pacific Coast and western interior regions is minimal.

Conclusion on Discreteness

    Based on the available information in the petition, scientific 
literature, and in our files regarding western snowy plover range and 
distribution, we conclude that the Pacific Coast WSP is markedly 
separate from other populations of the subspecies due to behavioral 
differences and that it, therefore, meets the requirements of our DPS 
policy for discreteness. Banding studies and resighting efforts 
demonstrate that during breeding, the Pacific Coast WSP segregates 
geographically from other members of the subspecies, even those that 
also winter on the Pacific coast. Although not absolute, this 
segregation is marked and significant.


    Under our DPS policy (61 FR 4722), once we have determined that a 
population segment is discrete, we consider its biological and 
ecological significance to the larger taxon to which it belongs. This 
consideration may include, but is not limited to, the following 
    1. Persistence of the discrete population segment in an ecological 
setting unusual or unique for the taxon,
    2. Evidence that loss of the discrete population segment would 
result in a significant gap in the range of the taxon,
    3. Evidence that the discrete population segment represents the 
only surviving natural occurrence of a taxon that may be more abundant 
elsewhere as an introduced population outside its historic range, or
    4. Evidence that the discrete population segment differs markedly 
from other populations of the species in its genetic characteristics.
    We evaluated available information to assess whether the 1993 
designation was consistent with the above factors or other relevant 
factors to explain why the Pacific Coast WSP is significant to the 
subspecies of western snowy plover. In this finding, we are only 
addressing the significant gap in the range of the taxon because that 
is the only significant criteria factor that applies.

[[Page 20617]]

Significant Gap in the Range of the Taxon

    One approach to assessing whether the Pacific Coast WSP constitutes 
a substantial portion of the western snowy plover subspecies (Pacific 
Coast, interior, and Gulf Coast) is to evaluate the size of the 
subspecies. Estimating size of a broadly yet patchily distributed 
subspecies like the western snowy plover is a difficult task to 
accomplish (Gorman and Haig 2002). At this time, our best available 
estimate of the subspecies' current total size is about 24,136 birds 
(Page et al. 1995a; P. Paton, University of Rhode Island, in litt. 
2004; Zdravkovic 2004; Gorman and Haig 2002; L. Kelly in litt. 2006; M. 
Jensen in litt. 2006; G. Page in litt. 2005) (see Table 1).
    The estimate in Table 1 of the total number of birds of the 
subspecies takes into account the following new data: Dr. Peter Paton 
recently revised his original published estimate of 10,600 birds for 
Utah (Page et al. 1995a) to 4,189 birds (P. Paton, in litt. 2004). 
Stenzel provides information that the 4,478 figure used to describe the 
Pacific Coast WSP population through the 2004 breeding season is likely 
an underestimate due to some areas in southern California not being 
surveyed (L. Stenzel, in litt. 2004a). The new observed estimated 
number of birds (3,695) is based on the 2005 breeding season (see Table 
1 above), which is approximately a 3 percent drop from Stenzel's 2004 
figure. Additionally, researchers in Texas believe that as many as 
1,000 plovers nested along the Texas Gulf coast in 2004, a substantial 
increase from the 100 reported by Page et al. (1995a) (Zdravkovic 
2004). We are not aware of what effect, if any, the 2005 hurricanes may 
have had on the Gulf coast plovers and their habitat.
    Monitoring results are not available for the interior and northeast 
coastal Mexico areas, and recent estimates have not been developed for 
several of the interior western snowy plover breeding areas. In light 
of this inconsistent survey coverage, we considered it appropriate to 
use the largest of the available estimate ranges available for the 
interior breeding plovers, so as not to overstate the significance of 
the Pacific Coast WSP. We acknowledge that the number of birds within 
the subspecies could be more or less than that indicated by the best 
available information. As presented in Table 1 above, the Pacific Coast 
WSP current population estimate is approximately 20 percent of the 
taxon's total estimated size (4,804 of 24,136 total birds). Therefore, 
we contend that using this conservative interpretation of the best 
available data, the 2005 Pacific Coast WSP constitutes approximately 20 
percent of the subspecies.
    The petition also states that because the range of interior western 
snowy plovers overlaps that of Pacific Coast WSP (by virtue of sharing 
winter ranges), they have ``ample opportunity to socialize, pair bond, 
and inter-breed.'' We agree that the potential exists for interactions 
to occur between wintering interior western snowy plovers and Pacific 
Coast WSP, but banding data indicate that such interactions occur at 
very low rates.
    The petition suggests, without any supporting evidence, that 
interior-nesting western snowy plovers would colonize the coastal 
breeding habitat if the Pacific Coast WSP were extirpated. As described 
earlier, the Pacific Coast WSP population declined during the 1970s to 
mid-1990s, leaving many historical breeding locations vacant throughout 
the coastal range, and even though ample habitat remained intact, it 
was not colonized by any plovers (coastal or interior). Analysis of the 
available banding data indicates that there is little interchange 
between the coastal and interior breeding populations (G. Smith, USGS, 
in litt. 2004; B. Andres, Service, in litt. 2005; J. Plissner, ABR 
Inc., in litt. 2005). Although low levels of breeding dispersal from 
the coast to the interior remain a possibility, the banding studies 
provide a high degree of confidence that any such dispersal is out of 
the coastal population, and not into it (C. Elphic, in litt. 2005). 
This is consistent with additional analysis indicating that the 
available banding data are adequate to conclude that an insignificant 
number of individual plovers disperse from interior breeding sites to 
coastal breeding sites (J. Plissner, in litt. 2005), and it is unlikely 
that interior breeding plovers would disperse to coastal breeding sites 
(B. Andres, in litt. 2005). We have no data documenting interior birds 
colonizing vacant coastal areas.
    This apparent lack of interchange between coastal and western 
interior breeding sites may be explained by the relatively high degree 
of site fidelity exhibited by this species. Breeding and winter site 
faithfulness vary between sites. Stenzel et al. (1994) report that 
plovers were faithful to their known breeding location in northern-
central coastal California about 59 percent of the time for females and 
84 percent of the time for males. Partial-absence (missing for a 
portion of the breeding season) from known breeding locations was more 
common than complete absence. Of the 147 birds observed moving during 
the breeding season, 25 females and 14 males moved from 50 to 708 miles 
(31 to 1,140 kilometers). All 147 birds remained within the coastal 
zone, either north or south of their previously known breeding 
location. There was no evidence of pair movements, only movements for 
individual plovers. Page et al. (1995a) present the following adult 
plover resighting rates at breeding locations between consecutive 
years: Monterey Bay, California, males 76.8 percent, females 65.8 
percent (Warriner et al. 1986); Mono Lake, California, males 77.8 
percent, females 44.9 percent (Page et al. 1983); Lake Abert, Oregon, 
males 64.1 percent, females 40.9 percent (Stern et al. 1990a). There is 
also evidence of fidelity to wintering areas. About two-thirds of 
plovers banded during the breeding season at Lake Abert, Oregon, were 
located on their coastal California or Baja California, Mexico, 
wintering areas for 2 subsequent years, and about one-third were 
subsequently located at least 3 years following banding (Page et al. 
    There is no evidence to indicate western interior populations would 
recolonize the Pacific coast if the listed population were lost. 
Therefore, such loss would remove 2,000 miles of coastline, stretching 
from Washington to Baja California, from the subspecies' breeding 
range. The Pacific coast constitutes the vast majority of coastal 
breeding habitat used by the subspecies (the rest being in southern 
Texas and northeastern Mexico), as well as the westernmost extent of 
the taxon's breeding range.
    We find that the Pacific Coast DPS is significant to the subspecies 
of western snowy plover because it comprises approximately 20 percent 
(one-fifth) of the subspecies' estimated population based on the 2005 
breeding window survey results. We conclude that the best available 
data demonstrate that the likelihood of pair bonding and interbreeding 
between the Pacific Coast WSP and the interior-nesting western snowy 
plovers is very low, and that there is no evidence indicating that 
interior breeding plovers would rapidly reestablish a viable breeding 
population along the Pacific Coast following the extirpation of the 
coastal population. Accordingly, loss of the Pacific Coast WSP would 
result in a significant gap in the breeding range of the taxon. It 
would constitute the loss of a substantial percentage of the 
subspecies, curtailing the taxon's current breeding range by 2,000 
miles of coast line.

[[Page 20618]]

DPS Status--Conclusion

    We find that the Pacific Coast WSP qualifies as a DPS under the 
Act, as recognized under our 1996 DPS Policy (Service and NMFS 1996a 
(61 FR 4722)). The Pacific coast population is discrete based on 
extensive banding data showing marked reproductive separation from 
other populations. Of the 4,170 plovers banded over the 12-year period 
with the most extensive banding and resighting surveys, 907 were 
resighted. Of these 907, 894 plovers (98.6 percent) were resighted 
within their natal or nesting site breeding ranges, 11 coastal plovers 
(1.2 percent) were resighted in the interior without nests, and 2 
plovers (0.2 percent) were resighted nesting outside of their original 
breeding range. These results suggest a marked reproductive separation 
between the Pacific Coast WSP and other interior western snowy plovers.
    The 1993 listing decision suggested that genetic differentiation 
between coastal and interior populations was likely. There is no 
evidence that such differentiation exists and existing information 
suggests coastal and interim populations do not markedly differ 
genetically. However, the banding data and the resighting efforts 
provide compelling information that during breeding, the Pacific Coast 
WSP segregates geographically from other members of the subspecies, 
even those that winter on the coast.
    The Pacific Coast WSP is also significant to the rest of the taxon 
because its loss would cause a significant gap in the range of the 
subspecies. The Pacific Coast WSP comprises approximately 20 percent of 
the subspecies estimated total size. We have no evidence that interior 
breeding plovers would reestablish a viable population along the 
Pacific coast following the extirpation of the coastal population. 
Accordingly, loss of the Pacific Coast WSP would result in a 
significant gap in the breeding range of the taxon.

Conservation Status

    When considering an action for listing, delisting, or reclassifying 

a species, we are required to determine whether a species is endangered 
or threatened based on one or more of the five listing factors 
identified in section 4(a)(1) of the Act. These factors are: (A) The 
present or threatened destruction, modification, or curtailment of its 
habitat or range; (B) over utilization for commercial, recreational, 
scientific, or educational purposes; (C) disease or predation; (D) the 
inadequacy of existing regulatory mechanisms; and (E) other natural or 
manmade factors affecting the continued existence of the species. 
Delisting a species must be supported by the best scientific and 
commercial data available. Delisting may occur only if such data 
substantiates that the species is neither endangered nor threatened for 
one or more of the following reasons: (1) The species is considered 
extinct; (2) the species is considered to be recovered; and/or (3) the 
original data available when the species was listed, or the 
interpretation of such data, were in error (50 CFR 424.11).

A. The Present or Threatened Destruction, Modification, or Curtailment 
of Its Habitat or Range

    The petition states that the ``western snowy plover has been very 
adaptive at exploiting opportunities to breed at new habitat that was 
created by humans including the Salton Sea, San Francisco Bay Salt 
Ponds, Central Valley agricultural ponds, and Batiquitos Lagoon.'' We 
agree with the petition's assessment as it relates to the Pacific Coast 
WSP. The western snowy plover is an early successional species that 
depends on dynamic habitat. As conditions change, the western snowy 
plover (including the Pacific Coast WSP) has the ability to colonize 
new sites. Because coastal habitats are dynamic, and change within a 
season or between seasons, the Pacific Coast WSP must adjust. However, 
our information shows that loss of nesting and wintering habitat 
remains one of the primary threats to the Pacific Coast WSP throughout 
its range. Causes of habitat loss include industrial and residential 
development, the spread of nonnative dune-stabilizing vegetation, human 
recreational use at levels that preclude nesting attempts, and various 
habitat alteration projects.
    Urban development permanently removes important nesting habitat 
above the high tide line. It is a major source of habitat loss in all 
three western U.S. coastal States, and particularly in southern and 
central California (Page and Stenzel 1981; Page et al. 1995a). 
Development may also affect beach accretion processes by removing areas 
in which sand normally accumulates. Other secondary effects include 
increases in human use of nearby beach areas (as with piping plover, 
Service 1996), and increased predation of eggs and chicks in some areas 
(see Predation section below). The Pacific coast is one of the fastest 
growing regions within the United States (Crossett et al. 2004).
    Another major source of habitat loss has been the spread of 
nonnative dune-stabilizing vegetation such as European beachgrass 
(Ammophila arenaria), which removes dune habitat by covering and 
anchoring dunes and preventing the free movement of wind-blown sand. 
Such grasses also provide cover for predators (Pickart 1997; Stern et 
al. 1991b). European beachgrass was introduced to the Pacific coast in 
the late 1890s as a means of stabilizing dunes to encourage 
development. A secondary effect of dune stabilization has been human 
development of beaches and surrounding areas (ODFW 1994). European 
beachgrass has since spread along the Pacific coast from British 
Columbia to Ventura County, California, invading every major dune 
system in the plover's range from Santa Barbara County north (Pickart 
1997). It is considered one of the primary causes of plover population 
decline in Oregon (Oregon Parks and Recreation 2003). Once established, 
it is extremely difficult and expensive to remove (Pickart 1997).
    American beachgrass (Ammophila brevigulata), which is native to the 
east coast and Great Lakes regions of North America, behaves similarly 
to European beachgrass and has become the dominant introduced 
beachgrass along much of the Washington coast (Washington Department of 
Fish and Wildlife 1995). In southern California, giant reed (Arundo 
donax) and South African iceplant (Carpobrotus edulis) have overgrown 
plover habitat in some areas.
    In southern California, large expanses of beach previously used for 
nesting are no longer available as habitat due to extensive 
recreational use by humans. Popular recreational beaches may be 
completely covered by human footprints, and may also undergo daily or 
weekly mechanized beach raking to remove trash and tide-cast wrack 
(Page and Stenzel 1981; Powell et al. 2002). Although the removal of 
trash is beneficial to plovers (see Predation section below), natural 
tide-cast wrack such as seaweed provides important habitat for plover 
prey populations such as flies and other invertebrates (Dugan et al. 
2000; 2003). Beach raking may also flush adults from nests and crush 
plover clutches, depending on the frequency of raking. Dugan et al. 
(2003) state that up to 99.4 miles (160 kilometers) of sand beach 
habitat south of Point Conception, California, are raked annually 
during the Pacific Coast WSP nesting season.
    The final category of habitat loss is habitat alteration projects, 
which include diversions and impoundments of streams and rivers, 
management of salt ponds for marsh habitat, dredging

[[Page 20619]]

and sand mining, and inappropriately designed breakwaters or beach 
nourishment projects. Waterway diversion and impoundment activities, 
such as the construction of seawalls and use of rip rap, can limit the 
delivery of sand and thereby lessen the extent of beach habitat. In 
southern California, blockage of lagoon mouths for road construction 
has prevented tidal flushing and associated salt pan formation, thereby 
eliminating important nesting habitat (Powell et al. 2002). Stream 
stabilization projects can interfere with the natural shifting of river 
mouths across the landscape, thereby allowing beachgrass (Ammophila 
spp.) and other vegetation to take root (Powell et al. 2002).
    Salt ponds, such as in the San Francisco, Monterey, and San Diego 
Bays in California, may be operated to the benefit or detriment of 
nesting plovers by allowing ponds to flood or dry at particular times 
(Page et al. 2003). In the San Francisco Bay, salt ponds that are 
managed for tidal marsh species, such as the salt marsh harvest mouse 
(Reithrodontomys raviventris) and California clapper rail (Rallus 
longirostris obsoletus), do not provide habitat for the plover (V. 
Bloom in litt. 2005). We are working with the California Department of 
Fish and Game and local landowners to develop a management plan for the 
area, which will best meet the needs of all the listed species in the 
area (M. Kolar, in litt. 2004).
    A survey of breeding plovers in Baja California, Mexico, noted two 
large salt works (one completed and one planned) at Laguna Oja de 
Liebre and Laguna San Ignacia, respectively. The survey noted numerous 
plovers continuing to nest at the completed facility, but also noted 
the loss of some nests and chicks there due to vehicular use of the 
area. The survey was unable to determine whether overall impacts from 
the two facilities would be detrimental or beneficial (Palacios et al. 
    Sand mining by heavy machinery, such as at Monterey Bay, 
California, eliminates nesting habitat within the area subject to 
mining, degrades nearby habitat by removing replenishing sand, and 
disturbs adjacent nesting due to noise and vehicle traffic (Guinon 
1988). Dredging can disturb nesting plovers, alter natural patterns of 
sand deposition, and encourage boat-related recreational activity in 
plover nesting areas. Alternatively, dredge tailings have served as 
important nesting habitat in Coos Bay, Oregon (Wilson-Jacobs and Dorsey 
1985). Breakwaters and beach nourishment projects also have the 

potential to benefit habitat by causing sand to accrete in nesting 
areas, but if designed incorrectly can also erode nesting areas or 
increase the slope of the beach and encourage invasive plants (Service 
    The petition offers some brief analyses of some of the threats to 
the Pacific Coast WSP addressed by the listing rule. The petition 
points out that many Pacific Coast WSP now breed in human created 
habitat ``including the Salton Sea, San Francisco Bay Salt Ponds, 
Central Valley agricultural ponds, and Batiquitos Lagoon.'' However, 
the Salton Sea and Central Valley agricultural ponds are outside of the 
breeding range of the coastal population (Service 1993 (58 FR 12864)). 
Use of Batiquitos Lagoon as a breeding site has increased by a total of 
14 birds since its restoration as a tidal marsh in 1996 (Port of Los 
Angeles 2003; L. Stenzel, in litt. 2004a). The San Francisco Bay Salt 
Ponds constitute genuine new, human-created habitat. In contrast to 
this addition, the species has lost 44 of its 53 known historical 
nesting sites in California prior to listing (Page and Stenzel 1981; L. 
Stenzel, in litt. 2004b), 2 of its 5 nesting locations in Washington, 
and 19 of its 29 nesting locations in Oregon (L. Stenzel, in litt. 
2004b). Based on the best available data, we believe the loss of 
habitat remains a significant threat to the population and the addition 
of nesting habitat at the San Francisco Bay Salt Ponds does not offset 
the full impact of this loss.
    In summary, habitat loss that negatively impacts Pacific Coast WSP 
has occurred in the past and continues to occur in the form of 
development, spread of nonnative dune-stabilizing vegetation, human 
recreational use at levels precluding nesting attempts, and habitat 
alteration projects. While some nesting habitat has been added at San 
Francisco Bay Salt Ponds that has benefited Pacific Coast WSP, it has 
not been sufficient to offset past and ongoing habitat losses.

B. Overutilization for Commercial, Recreational, Scientific, or 
Educational Purposes

    The petition did not provide any information about this threat.
    The only threat to Pacific Coast WSP from overutilization is 
potentially from scientific research. Currently, we issue permits under 
10(a)(1)(A) of the ESA to qualified individuals for nesting studies, 
surveys, banding, and protective management techniques such as nest 
exclosures. Disturbance of plovers is kept to a minimum through 
surveyor training and by minimizing time spent in nesting areas. While 
exclosures typically increase fledge rate, they also reveal nest site 
locations to predators, thereby potentially increasing the danger to 
adults and chicks as they leave the nest site to forage (Neuman et al. 
in press). Accordingly, effects of exclosures should always be closely 
monitored. Bands may occasionally result in leg injuries, including 
foot loss, possibly due to abrasion and subsequent swelling (Page in 
litt. 2005a). The percentage and severity of bandings resulting in 
injuries is not currently known, but is likely to be low based on 
numerous sightings of uninjured banded birds. Despite the low risk of 
injuries, banding remains the best technique to study population 
variables such as survival, recruitment, and dispersal, and appears to 
be the most effective way to monitor populations and determine the 
effectiveness of management strategies (Nur et al. 1999). We are 
monitoring banding injuries through our Section 10(a)(1)(A) recovery 
permit program, and have initiated an experimental program in the 
Monterey Bay area to determine if band position on the leg can decrease 
injuries by reducing the metal band's contact with sand. Sand wear on 
the metal band may cause the band's edge to become sharp, contributing 
to plover leg injuries. Additionally, sand grains can become lodged 
between the metal band and the plover's leg, resulting in irritation of 
the leg. We do not have any indication that leg injuries in plovers are 
occurring as a result of using plastic colored bands, which are 
    As noted in the petition, it is also theoretically possible for 
bands to increase the likelihood of predation, by increasing the 
visibility of the plovers. This is extremely difficult to test because 
there is no way of knowing the predation rate on unbanded birds. If 
such an effect does exist it would be more likely to apply to avian 
predators, since the primary mammalian predators (red fox (Vulpes 
vulpes) and coyote (Canis latrans)) tend to hunt in the evening and 
night. Plovers depend on their cryptic coloration and behavior to 
remain undetected by avian predators. Typically, plovers will crouch, 
flattening their profile to approaching aerial predators. Consequently, 
colored leg bands are covered by the crouching bird, making the bands 
largely undetectable to predators until the plover is forced to flush. 
The petition also notes that surveys and banding studies conducted at 
VAFB from 1995 to 2000 did not find birds banded at VAFB that were more 
than 3 years old; however, the study period was too short to find older 
birds except during 1999 and 2000. Several older birds that

[[Page 20620]]

hatched at VAFB were found during surveys in coastal California in 
2002, including 1 seven year-old, 2 six year-olds, 10 five year-olds, 
and 21 three or four-year olds (P. Nieto, SRS Technologies, in litt. 
2002). Most of these birds were found outside Vandenberg AFB, yet all 
were found within the coastal population. In summary, we conclude that 
overutilization is not a significant threat to the Pacific Coast WSP 
because research and monitoring are conditioned through our Recovery 
Permit program to reduce impacts, and steps have been taken to monitor 
and reduce band-related injuries.

C. Disease or Predation

    The petition did not provide any information about disease as a 
threat. However our information shows that West Nile virus, a mosquito-
transmitted pathogen that can infect numerous species of birds, 
reptiles, and mammals, has killed birds of various species in every 
coastal California county (USGS 2005a), as well as one coastal county 
in Oregon (Lane County) (USGS 2005b). The disease has not yet been 
reported in any Washington coastal counties (USGS 2005c), but will 
likely reach those counties in the near future, as it has spread 
rapidly across the United States from an initial introduction in New 
England (National Audubon Society 2004). The deadliness of the disease 
to birds varies by species (National Audubon Society 2003), but the 
disease has been identified in dead piping plovers (Charadrius 
melodius) and killdeer (C. vociferus), both closely related to snowy 
plovers (CDC 2004).
    Clark in litt. (2006) reported that 26 adult plovers either died or 
were found sick from the international boundary with Mexico to North 
Island Naval Air Station in San Diego Bay during the period of January 
through June, 2005. Although the cause of death remains uncertain, 
researchers believe an unknown toxin may be the cause. Tests have not 
identified the cause of sickness. We do not know if the illness extends 
within the Mexican portion of the Pacific Coast WSP. There is also a 
potential that ``Bird Flu'' (influenza) could also affect snowy plovers 
and other wildfowl, although Bird Flu has not been documented in the 
United States.
    The petition raised the issue of predation in both an historical 
and contemporary context. Specifically, the petition maintains that 
humans have been altering predator populations in California since the 
1700s when Spanish explorers began their movements along the Pacific 
Coast. Because predators have been removed from western snowy plover 
habitat, the petitioners believe that the plovers were able to 
``colonize areas where they had never lived before.''
    Predation has been found to be a major factor affecting nesting 
success across the range of the DPS. In San Diego County, California, 
crows (Corvus brachyrhynchos), ravens (C. corax), coyotes, and possibly 
Argentine ants (Iridomyrmex humilis) were the primary causes of nest 
failure in 1994, 1996, and 1997 (tidal flooding caused greater nest 
loss in 1995) (Powell et al. 2002). In Monterey County, nonnative red 
fox caused an increased number of nest failures from 1984 to 1991, 
while avian predators including shrikes (Lanius ludovicianus) and 
kestrels (Falco sparverius) had significant impacts on fledging success 
from 1996 to 1999 (Neuman et al., in press). A study of Oregon beaches 
identified predation by crows and ravens as the primary cause of nest 
loss in 1978 and 1979 (Wilson-Jacobs and Meslow 1984); while red fox, 
crows, and ravens caused low fledgling success rates across coastal 
Oregon from 1990 to 2003 (D. Lauten et al., in litt. 2004). Additional 
major predators include skunks (Mephitis mephitis) (Stern 1990b), 
merlins (Falco columbarius), northern harriers (Circus cyancus) (Page 
et al. 1997), dogs (Canis lupus), and cats (Felis cattus) (B. Farner 
pers. comm. in Powell and Collier 1994; Page 1988).
    Factors affecting predation levels on the Pacific Coast WSP include 
trash left near nesting areas; the availability of nearby cover for 
mammals or perches for birds; the existence of dependable food sources 
such as dumps and fish cleaning sites for gulls, ravens, crows, or red 
foxes; and the proximity of urban areas supporting dogs and cats 
(Service 2001). Plovers spend so much energy reacting to human 
disturbance that their ability to react appropriately to actual 
predators is lessened (Powell et al. 2002), either due to acclimation 
(Page et al. 1977) or stress and loss of foraging opportunities (Ruhlen 
et al. 2003).
    The petition asserts that humans may have helped plover populations 
by killing many plover predators. Intensive management and control of 
predators has likely led to an increase in plover numbers since the DPS 
was listed. The use of nest exclosures has increased hatch rates 
(Colwell et al. 2005; Lauten in litt. 2004; Fancher et al. in litt., 
2005), and the removal of predators at selected sites has improved 
fledging rates (Lauten, et al. 2006). However, predation still impacts 
reproductive success at numerous nesting locations (Persons and 
Applegate 1997; Colwell et al. 2005) and therefore remains a threat to 
the Pacific Coast WSP.
    In summary, disease and predation impact site-specific plover 
reproductive success and survival. Disease has become a recent, ongoing 
threat since the 1993 listing, resulting in the death of plovers from 
Monterey Bay, California, south to the Mexican border. We do not know 
the extent of the mortalities in the United States because not all of 
the carcasses are found due to predation, wind blown sand, and tidal 
action. In addition, we do not have information regarding the extent of 
plover deaths related to disease or toxins in Mexico. Deaths in the 
United States will continue to be monitored, and funding has been 
appropriated to help determine the cause of death. Predation continues 
to be a major factor affecting nesting success, and thus constitutes a 
threat to the Pacific Coast WSP. Management actions implemented largely 
in response to the listing have controlled many factors affecting 
predation. For example, the use of nest exclosures has significantly 
increased nest hatch rates by reducing predation (Colwell et al. 2005; 
Fancher et al. in litt., 2005), and predator management improves 
fledging success and reproductive rates (Lauten et al. 2006). Current 
site specific predator management has reduced the significance of 
predation to the Pacific Coast WSP; however, if management actions are 
no longer implemented, plover populations would likely drop at several 
locations, possibly affecting population viability within key areas or 
on the rangewide scale.

D. The Inadequacy of Existing Regulatory Mechanisms

    The petition did not provide any information about this threat. Our 
information is discussed below.

Federal Laws

United States

    Since the species is currently listed under the Endangered Species 
Act of 1973, as amended (16 U.S.C. 1531 et seq.), this law is the 
primary mechanism for protecting the Pacific Coast WSP. Multiple 
sections of the Act contain provisions that promote conservation of 
listed species. Section 2(c)(1) states the policy of Congress that all 
Federal agencies shall seek to conserve listed species and utilize 
their authorities to further purposes of the Act. Section 4 outlines: 
The threat factors for which a species can be listed; the formation of 
recovery teams and development of recovery plans to address those 
threats; reclassifications and delisting, and post

[[Page 20621]]

delisting monitoring requirements; and protective regulations (special 
rules) for threatened species. Section 5 discusses conservation of 
listed species through land and water acquisition. Section 6 calls for 
cooperation with the States by entering into management and cooperative 
agreements, and providing funding to those States with cooperative 
agreements. Section 7 requires Federal agencies to carry out programs 
to conserve listed species and to consult with the Service to ensure 
that their actions do not jeopardize the continued existence of listed 
species. Section 9 makes it unlawful to import, export, take, or 
violate any regulation pertaining to listed wildlife, and on Federal 
lands, plants. Section 10 authorizes: Scientific permits for research 
or to enhance the survival and recovery of listed species; incidental 
take permits based on a habitat conservation plan that will not 
appreciably reduce the likelihood of survival and recovery of the 
listed species; and experimental populations outside a species' current 
range. Section 11 assesses civil and criminal penalties for violations 
of the Act or its implementing regulations. These provisions are 
applicable to the protection of a species while it is on the Federal 
List of Endangered and Threatened Wildlife and Plants. If removed from 
the list, the Pacific Coast WSP would no longer receive the protections 
of listing or from the designation of critical habitat. Federal 
agencies would no longer consult with us concerning the impacts of 
actions that may affect Pacific Coast WSP to ensure that such actions 
do not jeopardize the continued existence of Pacific Coast WSP, nor 
would individuals seek section 10(a)(1) permits for private actions 
affecting the species. It is possible that, in the absence of the 
Federal listing, many state/local regulations and programs that 
currently protect the Pacific Coast WSP would be repealed and 
    The Migratory Bird Treaty Act (MBTA) (16 U.S.C. 703 et seq.), 
protects Pacific Coast WSP, and their eggs and nests, from being 
killed, taken, captured, or pursued. However, it does not protect 
habitat except to the extent that habitat alterations would directly 
kill birds.
    The Clean Water Act (CWA) (33 U.S.C. 1251 et seq.) prohibits 
unpermitted discharge of pollutants (including dredge and fill 
material) into ``the waters of the United States'' (33 U.S.C. 1311, 
1362), including most rivers, streams, wetlands, and the ocean below 
high tide (33 U.S.C 1362; 33 CFR 328.3, 328.4). The CWA affects 
numerous potential threats to Pacific Coast WSP, including dredging and 
most sand-mining operations, construction of jetties and breakwaters, 
beach nourishment projects, oil and contaminant spills, sewage 
discharge, construction in many ephemeral pool areas forming in dune 
hollows, and discharge of fill material capable of altering river flows 
and sand deposition. Permits for dredge and fill discharge, including 
that resulting from construction, are governed by the Army Corps of 
Engineers (Corps). Permits for actions likely to affect listed species 
receive greater scrutiny, and no discharge of dredged or fill material 
shall be permitted if it jeopardizes the continued existence of a 
listed species or results in the likelihood of the destruction or 
adverse modification of critical habitat (40 CFR 230.10).
    Section 10 of the Rivers and Harbors Act (33 U.S.C. 403) requires a 
permit from the Corps for any structure or work that takes place in, 
under, or over a navigable water or wetland adjacent to navigable 
waters of the United States (Army Corps of Engineers, in litt. 2004). 
As with the CWA, permits for actions likely to affect listed species 
receive greater scrutiny.
    The National Environmental Policy Act, as amended (42 U.S.C. 4321-
4347), requires that each Federal agency prepare an environmental 
impact statement on the potential environmental consequences of major 
actions under their jurisdiction. This does not preclude the agency 
from choosing environmentally damaging actions, but it does disclose 
the existence of such actions and any less environmentally damaging 
    The Coastal Zone Management Act (CZMA) (16 U.S.C. 1451-1464) helps 
fund State development of comprehensive programs to protect and manage 
coastal resources, and requires Federal agencies to act consistently 
with those programs.
    Finally, the National Wildlife Refuge System Improvement Act of 
1997 (Pub. L. 105-57) establishes the protection of biodiversity as the 
primary purpose of the national wildlife refuge system. This has lead 
to various management actions to benefit Pacific Coast WSP at national 
wildlife refuges in the three Pacific coastal States. For instance, the 
Don Edwards-San Francisco Bay National Wildlife Refuge has acquired 
lands and is working with the Cargill Salt Company to restore historic 
salt marsh around San Francisco Bay (M. Kolar, in litt. 2004). Other 
coastal refuges in these States provide benefits to plovers and are an 
important component of the recovery strategy for the Pacific Coast WSP.


    Other than the MBTA, the Pacific Coast WSP has no regulatory 
protection in Mexico.
    Summary of Federal Regulations. Other than the Endangered Species 
Act and MBTA, existing U.S. Federal laws and regulations only provide 
protection for the Pacific Coast WSP in specific cases, such as where 
the species may be impacted by dredge and fill projects. These 
protections are therefore applied sporadically throughout the range of 
the Pacific Coast WSP, and are currently inadequate to comprehensively 
address the threats to the species. Absent the protection accorded due 
to its listed status, these statutes and regulations will not provide 
sufficient minimal protections for the Pacific Coast WSP. Mexican laws 
and regulations are also inadequate to comprehensively address the 
threats to the species.

State Laws

    State lands administered by the California Department of Parks and 
Recreation, California Department of Fish and Game, Oregon Department 
of Fish and Wildlife, Oregon Parks and Recreation Department, 
Washington Department of Fish and Wildlife, Washington State Parks and 
Recreation Commission, and Washington Department of Natural Resources 
play an important role in conservation of western snowy plovers and 
their habitats. Approximately 21 percent, 12 percent, and 9 percent of 
the breeding population of western snowy plover in California, Oregon, 
and Washington, respectively, occurs on State lands. Intensive 
management for western snowy plovers occurs at a number of State-owned 
plover habitat areas.


    The western snowy plover is a Bird Species of Special Concern in 
California. This designation confers no regulatory advantage, but is 
associated with recommendations and increased visibility to management 
agencies (Remsen 2003).
    The California Coastal Management Program, administered by the 
California Coastal Commission in accordance with the CZMA includes a 
system of: (1) Coastal permits and appeals; (2) planning and 
implementation of local coastal programs; and (3) Federal consistency 
review. Most local coastal programs and general plans were completed 
prior to the 1993 Pacific Coast WSP's listing; therefore, many do not 
reflect protective measures specifically for the western snowy plover. 
However, it is likely that the

[[Page 20622]]

Pacific Coast WSP has benefited from actions, such as limiting 
development, regulated by the California Coastal Commission in some 
    In California, biannual western snowy plover coordination meetings 
are held among Federal and State agencies and Point Reyes Bird 
Observatory staff to track the breeding population of western snowy 
plovers in the Monterey Bay area. Meetings of this working group have 
been ongoing since 1991. Management needs such as exclosures, symbolic 
fencing, predator control, removal of exotic vegetation, and 
acquisition of key sites are considered and planned through this forum. 
A working group for San Luis Obispo and Santa Barbara Counties, 
consisting of site managers, western snowy plover monitors, and our 
staff, began meeting twice annually in 2001 to address management needs 
of the Pacific Coast WSP. The group is also coordinating window surveys 
of breeding and wintering birds in that region.
    Management actions of California State Parks along with other 
entities. The California State Parks has been a leader with habitat 
restoration, monitoring, and the use of symbolic fencing to direct 
human use at the beach. Plovers nested at Manchester State Beach for 
the first time in 2003, and returned in 2004. A single plover nest was 
documented at Gold Bluffs Beach in 2004, which was the first since the 
early 1980s. Humboldt County Parks has enacted a ``plover friendly'' 
ordinance to reduce impacts to breeding plovers. The Bureau of Land 
Management and the California Department of Fish and Game also manage 
winter and breeding habitat, and have conducted habitat restoration and 
human disturbance management (Colwell, et al. 2005).
    The California State Parks and the Point Reyes Bird Observatory 
have developed some of the leading outreach tools, such as the docent 
program implemented at Half Moon Bay State Beach, that have been found 
to be effective rangewide. California State Parks and the Point Reyes 
Bird Observatory have worked cooperatively with the National Park 
Service (Golden Gate National Recreation Area and Point Reyes National 
Seashore), the Salinas River National Wildlife Refuge (NWR), and the 
California Department of Fish and Game to manage human use in plover 
wintering and breeding habitat adjacent to large population centers 
(Page, et al., 2005).
    The Salinas River NWR, along with California State Parks and Point 
Reyes Bird Observatory, has made significant achievements in habitat 
and predator management. Symbolic fencing, nest exclosures, lethal and 
nonlethal methods of predator control, and outreach techniques have all 
been pioneered in this area. Plovers had record reproductive success at 
Monterey Bay during 2003 (Page, et al. 2005). Management actions at 
Oceano Dunes State Vehicular Recreation Area have also bolstered the 
plover numbers. The California State Parks is developing a Habitat 
Conservation Plan (HCP) for plovers for the San Luis Obispo District, 
including Oceano Dunes State Vehicular Recreation Area.


    The western snowy plover is listed as threatened under the Oregon 
Endangered Species Act (Oregon Administrative Rules (OAR) 635-100-
0125). This OAR protects against actions that would directly kill 
plovers (OAR 635-100-0100, 41 ORS 498.026), and also requires the 
establishment of ``survival guidelines,'' which in the plover's case 
refers to a conservation program defined at OAR 635-105-000. The 
program authorizes the preparation of several site-specific management 
plans for State lands. State agencies must consult with the Department 
of Fish and Wildlife (ODFW) as to whether their actions are consistent 
with the local management plan (if one exists), or if not, whether the 
actions will appreciably reduce the likelihood of survival or recovery 
of the western snowy plover. The action agency makes the final 
determination. At this time, the local management plans are not 
completed, but an interagency group has been formed to work on them, as 
well as on a Statewide habitat conservation plan under section 10 of 
the Act, and on coordination of various protective management efforts 
such as predator control and monitoring (Lauten, et al. 2006).
    Oregon has also developed a coastal zone planning system consistent 
with the CZMA, which includes several elements beneficial to western 
snowy plovers and their habitat. The system requires local 
jurisdictions to develop local comprehensive plans and implementing 
measures according to a set of 19 goals. Those goals include 
requirements for protection of wildlife habitat, including estuarine, 
beach and dune ecosystems, and also encourage planning and coordination 
among agencies.


    The snowy plover is listed as endangered under the State endangered 
species regulations (Washington Administrative Code 232-12-14), which 
authorizes the preparation of a recovery plan for the species. The 
State's Shoreline Management Act (RCW 90.58), which enacts coastal zone 
management programs applicable to the CZMA, also provides some 
protection to the species by requiring local planning efforts to 
regulate coastal development. The Shoreline Management Act exempts 
single family housing construction from the coastal permit process 
(WDOE 1999).
    In summary, while State laws and regulations provide some level of 
protection for the Pacific Coast WSP, those protections are not 
consistent throughout the Pacific Coast WSP's range. As a result, these 
existing regulatory mechanisms do not address threats to the Pacific 
Coast WSP to such an extent that it is no longer in need of the 
protections of the Act.

Local Regulations

    In addition to various protections for coastal habitat enacted 
under the CZMA related statutes (see above), several local 
jurisdictions, such as Half Moon Bay, California, and Coos and Curry 
Counties, Oregon, have enacted regulatory policies specifically to 
protect the western snowy plover. However, based on results of a 
questionnaire sent to local governments, it appears that other local 
planning efforts generally do not take the snowy plover into account 
(Service 2001). In totality, existing local regulations are inadequate 
to address the Pacific Coast WSP's threats to such an extent that it is 
no longer in need of the protections of the Act.
    Many of these Federal, State, and local regulatory mechanisms were 
in place prior to the Federal listing of the Pacific Coast WSP, and 
were not adequate to prevent the loss and degradation of Pacific Coast 
WSP habitat and decreases in Pacific Coast WSP population numbers, and 
therefore, not adequate to preclude the need to list the Pacific Coast 
WSP under the Endangered Species Act (Service 1993). While some 
significant gains in protection have been made by entities such as 
California State Parks, overall, we find that the existing regulatory 
mechanisms, beyond the listing itself, have not addressed the threats 
facing the Pacific Coast WSP, and are therefore not sufficiently 
adequate to warrant delisting of the Pacific Coast WSP. The Endangered 
Species Act provides comprehensive conservation of the Pacific Coast 
WSP and provides the mechanisms under which we can continue to work 
with the States and local governments to implement actions to recover 
the species. Delisting would

[[Page 20623]]

remove this most comprehensive means of achieving the eventual recovery 
of the species. We thus conclude that the regulatory mechanisms in the 
absence of listing are inadequate to address the threats to the Pacific 
Coast WSP to such an extent that it is no longer in need of the 
protections of the Act.

E. Other Natural or Manmade Factors Affecting Its Continued Existence

    The petition did not provide any information about this threat. 
However, our information shows that most Pacific Coast WSP nesting 
areas occur on unstable sandy substrate which results in weather-
related nest loss, a fairly common natural phenomenon. High tides and 
strong winds cause nest losses annually. Events such as extreme high 
tides (Wilson 1980; Stenzel et al. 1981), river flooding (Stenzel et 
al. 1981; Colwell et al. 2004), and heavy rain (Wilson 1980; Warriner 
et al. 1986; Page 1988) have been reported as causes that destroy or 
wash away nests. The annual percentage of total nest loss attributed to 
weather-related phenomenon has reached 15 to 38 percent at some 
locations (Wilson 1980; Warriner et al. 1986). Severe winter storms may 
also significantly impact plover populations. For example, after a 
series of severe storms during the winter of 1997 to 1998, coinciding 
with an El Ni[ntilde]o event (a collection of oceanic and atmospheric 
phenomena involving shifted trade winds and warmer ocean waters), the 
plover breeding population at VAFB suffered a 10 to 30 percent decline 
(Applegate and Schultz 1999). Additionally, erosion of beach sand or 
flooding of coastal lagoons or river bars may reduce habitat available 
for nesting in some years (Colwell et al. 2005), which likely forces 
some plovers to nest in marginal habitat where nesting success is 
    Disturbance of nesting or brooding plovers by humans and domestic 
animals is a major factor affecting nesting success. Plovers leave 
their nests when humans or pets approach too closely. Disturbance 
distances that may cause plovers to leave their nests vary widely, from 
about 3 to 200 meters (10 to 656 feet) in a Point Reyes, California, 
study (Page et al. 1977), and from about 3 to 50 meters (10 to 164 
feet) in a study at VAFB, California (Fahy and Woodhouse 1995). Humans 
accompanied by dogs tend to elicit stronger avoidance responses than 
humans alone (Page et al. 1977; Fahy and Woodhouse 1995; Lafferty 
2001). Dogs may also deliberately chase plovers and trample nests 
(Lafferty 2001). Repeated flushing of incubating plovers exposes the 
eggs to the weather, interrupts foraging, and depletes energy reserves 
needed by the adult, which may result in reductions to nesting success 
during the breeding season and in reduced survivorship during the 
winter (Lafferty 2001).
    Surveys at VAFB, from 1994 to 1997, found the rate of nest loss on 
southern beaches to be consistently higher than that on north beaches 
where recreational use was much lower (Persons and Applegate 1997). 
Ruhlen et al. (2003) found that increased human activities at Point 
Reyes, California, beaches resulted in a lower plover chick survival 
rate. Nests may also be lost directly from human recreational 
activities. Warriner et al. (1986) documented a 14 percent loss of 
clutches at a Monterey Bay site due to being stepped on, driven over, 
or deliberately collected. Motorized vehicles, where allowed onto 
stretches of beach used by plovers, can stress or directly kill adults 
and chicks, as well as destroy nests and eggs (Colwell et al. 2004). 
Plovers' cryptic coloration and habit of crouching in depressions such 
as tire tracks make them particularly susceptible to being hit by 
vehicles. They are especially vulnerable at night, when they are most 
difficult to see. Recent efforts in various areas have been implemented 
to isolate nesting plovers from recreational beach users through the 
use of docents, symbolic fencing, and public outreach, and have 
correlated with higher nesting success in those areas (Page et al. 
2003; K. Palermo, in litt. 2004; G. Page, in litt. 2004a).
    Motor vehicles that are driven in breeding habitat may result in 
the crushing of eggs, chicks, and adults; cause abandonment of nests; 
separate chicks from brooding adults; and provide a source of 
considerable stress and disturbance to plover family groups and 
wintering plovers (J. Myers, in litt. 1988; Stern et al. 1990b; Widrig 
1980). In Baja California, Mexico, vehicle traffic at Laguna Ojo de 
Liebre has destroyed plover nests and chicks, and the level of off-road 
vehicle use was considered ``heavy'' at 3 of 16 nesting areas surveyed 
(Palacios et al. 1994). In addition to recreational vehicles, vehicles 
used for military activities have also caused western snowy plover 
mortality (Powell et al. 1995; Powell et al. 1997; Persons 1994).
    Additional recreational activities with potential impacts similar 
to those discussed for pedestrians include commercial and surf fishing, 
clamming, campfires, and camping. If conducted near a nest, these 
activities may result in long-term disturbance and ultimately nest 
abandonment (Colwell et. al. 2003).
    Plover populations can be negatively impacted by oil spills 
(Persons and Applegate 1997; U.S. Bureau of Land Management 2001; Kritz 
1999). Oiled plovers lose their ability to regulate their body 
temperature and often die of hypothermia or exposure. Additionally, 
oiled adults can pass oil onto eggs if they are incubating. Oil on eggs 
limits their ability to breathe, and introduces toxic hydrocarbons. 
Likewise, oiled adults that attempt to preen inhale and ingest 
hydrocarbons. Invertebrate populations are likely reduced as a result 
of beaches being oiled, reducing the available plover prey base. Oiled 
invertebrates may also be another source of hydrocarbon ingestion for 
plovers. During the 1990s, at least six oil spill incidents in 
California and one in Oregon resulted in adverse impacts to plovers. 
For example, in February 1999, the freighter New Carissa went aground 
near the North Jetty of Coos Bay, Oregon, leaking oil from the stern 
section on repeated occasions (U.S. Bureau of Land Management 2001). 
The incident oiled over 50 percent of the Oregon wintering population 
of western snowy plover (Kritz 1999). Had this occurred during nesting 
season at one of the major nesting sites the impacts (both from the oil 
directly and from subsequent disturbance due to the spill response 
crew) could have been extremely severe. Plovers may also be affected by 
chronic oil pollution not easily attributable to specific spills. 
Intermittent oil spills from unknown sources have been noted on central 
California beaches for decades. The cause of some of these spills, such 
as those related to periodic oil leakages from the sunken vessel S. S. 
Jacob Luckenbach, have recently been identified, while the source of 
others remains a mystery (Hampton et al. 2003).
    In summary, we conclude that unmanaged human disturbances and 
impacts related to oil spills remain a significant threat to the 
Pacific Coast WSP. Unmanaged human disturbances that negatively impact 
Pacific Coast WSP primarily include disturbance of nesting or brooding 
plovers by humans and domestic animals and motorized vehicle use. Oil 
spills and their associated clean-up can result in reproductive 
failure, direct mortality and injury from being oiled, and 
contamination of food sources. The significance of an oil spill to 
plovers depends on the extent of the spill, the material spilled, and 
the timing of the spill in relation to plover habitat and breeding 

[[Page 20624]]

Status of the DPS--Conclusion

    Threats to the Pacific Coast WSP remain essentially the same as at 
the time of its listing in 1993. However, the magnitude of the threats 
has been reduced through active management afforded by protections 
under the Act, with a resultant increase to the overall Pacific Coast 
WSP population. Despite the reduction in the threats' magnitude 
relative to the time of listing, the Pacific Coast WSP is still at 
risk. The most important threats are ongoing habitat loss and 
fragmentation; mortalities, injuries, and disturbance resulting from 
human activities; and lack of comprehensive State and local regulatory 
mechanisms throughout the range of the WSP. Although overall increases 
in plover numbers (which can be attributed to management actions 
currently being implemented) have been observed, plover population 
sizes are low or plovers are absent throughout parts of their 
historical range in Washington, Oregon, and California. Accordingly, we 
find that the Pacific Coast WSP continues to qualify as a threatened 
species under the Act (see also Finding section below).
    We also note that: because some of the threats have been reduced, 
the estimated WSP population levels in the United States have increased 
over the last 4 years (L. Stenzel, in litt. 2004a); management actions 
in several areas appear to be effective (Page et al. 2003; G. Page, in 
litt. 2004a); and numerous local management plans, habitat conservation 
plans, and integrated natural resource management plans have been 
implemented or are in the planning stages (Lauten et al. 2006; Colwell 
et al. 2005). We find these trends and management actions encouraging. 
We believe significant progress has been made toward recovery in a 
relatively short period of time (approximately 10 years), and that 
continued implementation of recovery actions that reduce the remaining 
threats could justify a delisting of the Pacific Coast WSP in the near 
future. In the interim period, we are providing a mechanism that will 
afford regulatory relief for areas that are contributing to recovery 
now. In today's issue of the Federal Register, we have published a 
proposal for a special rule under section 4(d) of the Act that would 
exempt certain actions in certain areas from the section 9 take 
prohibitions of the Act, throughout the range of the DPS. Please see 
the Proposed Rules Section of today's Federal Register for more 
information on this proposal.


    We have carefully assessed the best scientific and commercial 
information available regarding the past, present, and future threats 
faced by this species. We reviewed the petition, available published 
and unpublished scientific and commercial information, and information 
submitted to us during the public comment period following our 90-day 
petition finding. This finding reflects and incorporates information we 
received during the public comment period and responds to significant 
issues. We also consulted with recognized western snowy plover experts 
and Federal and State resource agencies. Based on this review, we find 
that (1) the Pacific Coast WSP constitutes a valid DPS, which is both 
discrete and significant under our DPS policy, (2) delisting of the 
Pacific Coast WSP is not warranted due to continued existence of 
threats to the DPS and its habitat, and (3) the DPS should remain 
classified as threatened. We reviewed the available data and 
information on the life history and ecology of the Pacific Coast WSP 
and did not find convincing information that the plover was listed in 
error or that the threats have changed to such an extent as to warrant 
    In making this determination we have followed the procedures set 
forth in section 4(a)(1) of the Act and regulations implementing the 
listing provisions of the Act (50 CFR part 424). We recognize that in 
the past there have been declines in the distribution and abundance of 
the Pacific Coast WSP, primarily attributed to habitat loss and 
alteration. Much of the Pacific Coast WSP's historic habitat and range 
has been lost or degraded. There is substantial information indicating 
that plover habitat continues to be threatened with loss and 
fragmentation (listing Factor A) resulting in a negative impact on 
plover distribution and abundance. Mortalities and injuries resulting 
from human activities that cause continued habitat loss and disturbance 
(listing Factors A and E) may be frequent enough to prevent local 
recovery of populations, or prevent the re-occupation of suitable 
habitat. Although overall increases in plover numbers (which can be 
attributed to management actions currently being implemented) have been 
observed, plover population sizes are low, and plovers are absent 
throughout parts of their historical range in Washington, Oregon, and 
California. Although there are some local exemptions, current 
regulations (particularly if the protections of the Act are removed) 
provide insufficient certainty (listing Factor D) that conservation 
efforts will be implemented or that they will be effective in reducing 
the level of threat to the Pacific Coast WSP throughout the listed 
    Therefore we believe that the Pacific Coast WSP DPS is still likely 
to become endangered within the foreseeable future. In addition, we 
therefore believe (per the analysis conducted as part of the 12 month 
status review and the 5-year review) that the Pacific Coast WSP should 
remain classified as a threatened species, because it is not extinct, 
it is not considered to be recovered, and the original data used for 
classification were not in error.
    While the finding reflects the analyses conducted to fulfill our 
responsibilities under sections 4(b)(3)(A) (status review) and 4(c)(2) 
(5-year review) of the Act, we request that you submit any new 
information, whenever it becomes available, for this species concerning 
status and threats. This information will help us monitor and encourage 
the conservation of this species. We intend that any action for the 
Pacific coast DPS of the western snowy plover be as accurate as 
possible. Therefore, we will continue to accept additional information 
and comments from all concerned governmental agencies, the scientific 
community, industry, or any other interested party concerning this 

References Cited

    A complete list of all references cited is available on request 
from the Arcata Fish and Wildlife Office (see ADDRESSES).


    The primary author of this document is staff from the Arcata and 
Sacramento Fish and Wildlife Offices (see FOR FURTHER INFORMATION 


    The authority for this action is the Endangered Species Act of 
1973, as amended (16 U.S.C. 1531 et seq.).

    Dated: April 13, 2006.
H. Dale Hall,
Director, Fish and Wildlife Service.
[FR Doc. 06-3792 Filed 4-20-06; 8:45 am]